Wikibon Blog

Let’s take a hypothetical customer who is looking to build a new data center and they would like to embrace the latest and greatest technologies.  Can they construct an entire environment built with a Converged Network – an all-Ethernet environment?  This post will focus on the technology and ecosystem.

The Single Network

First of all, by convergence, I am talking about having all traffic going over a single wire.  Existing environments today have separate networks for security, management and traffic requirements (multiple Ethernet connections and/or a mixture of Ethernet, Fibre Channel (FC) and InfiniBand).  If we can get down to a single wire (of course with proper high availability), we can save power, cooling, space and most importantly operationally we simplify the environment which will allow for mobility of virtualized environments.  The “winner” of the single network has been known for many years – the answer is ETHERNET – the industry has known this for many years, but there have been limitations (some technical, some organizational).  With 10 Gigabit Ethernet, there is the opportunity to change things.  If you are already using NAS or iSCSI, it is simply a matter of moving to the faster speed and considering having multiple traffic types on a single wire (which is different that 1Gb iSCSI configurations).  For FC customers, FCoE is the option that will allow large storage environments to migrate into Ethernet without disrupting their current processes.

The Vendor Discussion

Most vendors discussing FCoE fall into one of 2 camps:

• Blue Sky: “no barriers – every solution works great today – buy it all now”
• FUD: “sure we have FCoE, but there are standards issues, and limitations – why don’t we do a beta for the next 18 months”

It’s not all bad, there are some good discussions going on in the blogosphere on some of the advanced functionality that is being created.  If you’re ready for an advanced topic on FCoE, there have been some great posts digging into TRILL (Layer 2 multipathing created in the IETF standards group; replaces Spanning Tree Protocol) including from Brad Hedlund (Cisco) and Greg Ferro (EtherealMind).

Reality

The reality is that most customers are still learning the basics on FCoE.  At EMC World last month, I gave an introductory level presentation on FCoE and Converged Networks and between the two sessions had almost one thousand attendees, the majority of which this was the first time they were hearing details on FCoE.

Let’s look at some of the “limitations” that might prevent customers from going All-Ethernet:

• Operating Systems: today it is primarily Windows, Linux and VMware – UNIX is coming soon, Mainframe is a big TBD
• Cabling – the #1 issue for the person building the data center is that the infrastructure can be used for the next 5-10 years. There are options at 10Gb Ethernet for copper, but in the next 5-10 years 40Gb and 100Gb must be considered, so is Copper dead?
• Multi-hop configurations are coming – today you can do a blade server switch to an edge switch, more flexibility coming soon (see Joe Onisick’s post on muti-hop FCoE)
• Only Edge/Access Layer switches – director class products which could be either Ethernet or FC directors with FCoE capability are not yet available. Be on the lookout to make sure that these products have the same high availability features as are available with FC solutions today
• Native FCoE is available from NetApp today and is expected from other vendors soon – storage is typically attached to a director in the core, so expect the FCoE director products and native FCoE storage to come out around the same time

As you can see, the technical issues are all being worked and should be resolved in the next 6-12 months.  The ecosystem is growing for Lossless Ethernet which will address customer concerns about vendor lock-in – there needs to be more options than just Cisco and there will be.

The answer to the question – can you build an All-Ethernet Data Center with FCoE is a qualified yes if you are planning for a new data center for the end of 2010 or in 2011. Exact configurations and settings are still be tested and best practices are starting to be written now.  Turnkey rack-based solutions that take advantage of FCoE will simplify deployments. IBM, HP and Cisco (and Vblocks from the VCE initiative from Cisco, EMC and VMware) all have Rack Area Networks (RAN) that are architected with Ethernet as the converged network that can run FCoE.  We are still very early in the adoption curve, the technology barriers are coming down and it will be the organizational and operational issues that will decide if FCoE becomes a component of customer data centers.

For more background on FCoE, see the archive on my personal blog.  Comments and discussions are always welcome.